Drying Kinetics and Microstructural and SensoryProperties of Black Chokeberry (Aronia melanocarpa) as Affected by Drying Method

Drying kinetics and microstructural (porosity and total pore volume) and sensory properties of chokeberries dried by different techniques and routes were investigated in this study. Porosity and total pore volume were assessed by X-ray microtomography, while sensory profiles were generated using a trained panel. Page model was successfully used to describe the drying kinetics of chokeberry fruits. The shortest drying time was that of vacuum-microwave drying, VMD (mean of 54 min). The treatments leading to the highest values of porosity were freeze drying (FD, 76 %) and VMD (39 %); samples dried using these two techniques also showed low value of hardness and cohesiveness. Convective predrying (CDP) followed by vacuum-microwave finishing drying (VMFD) reduced both porosity and total pore volume. On the other hand, osmotic dehydration, as a combined technique, increased both porosity and total pore volume. Osmotic dehydration significantly increased the crispiness of the dried samples by creating high temperature and consequently final low moisture content. The best treatment from a sensory point of view was VMD at 360 W. This treatment led to significant and simultaneous reductions of undesirable high intensities of sourness, bitterness, and astringency, but without generating undesirable burnt notes. Excessive sourness, bitterness, and astringency, typical of fresh chokeberry, usually reduce consumers' acceptance and preclude its wide use in the food industry.